A lot of people pride themselves on being "balanced". You know those people. They tell you that they watch both Fox News and MSNBC, read both Richard Dawkins and Karen Armstrong, in an attempt to get both sides of the issue (that way you can't "label" them). It's as if, by watching two things that are biased towards different opinions, they're getting all the information and are more educated (a.k.a. they're holier than thou). But, you must know, this culture of hearing both sides of the issue is silly and in at least one case dangerous.
By listening to "both sides of the argument" you are committing a logical fallacy called the "false dilemma". You create a situation where only two alternatives are considered, when in fact there may be many approaches.
If you have a debate, and assume there are only two sides, you've committed that fallacy. If there is an issue politically, then if you only look for Democratic and Republican responses then you've committed that fallacy. If you advocate that alternative theories, i. e. Intelligent Design, should be taught alongside evolution, you've assumed that there aren't any other viewpoints (there are).
An easy solution, follow the evidence and draw conclusions from them: don't spend a lot of time listening to arguments.